My take on most of the modern MMOs out there:
EVE Online
Extremely hard to get in to, unless you know people already playing then you will need to make friends fast or get in an active Corp. fast if you are going to enjoy this game. The quality is fantastic, atmosphere and an authentic feeling of being in a massive galaxy in an awesome sci fi setting.
The 'leveling' is a superb idea, choose what way to develop your character and he will learn skills over time if you are online or not. This means you will plan learning routes and really get in to how you will develop your character. I spent many hours just planning and sorting how I am improving my character.
I don't have any experience of high level or PvP because despite many tries I could not get attached to this game.
World of Warcraft
Without a doubt the best MMO on the market right now. The content is massive, the leveling process one of the most fun and fleshed out in any MMO out there. The PvP system is one of the best although as a new player you will probably only ever get to above average in PvP now because the length some people have played. End game can feel kind of grindy and extremely demanding of your time much like any other MMO. Graphics are becoming very dated but the overall aesthetics and atmosphere are still very good.
I haven't played for almost a year because I have played it so much you begin to hate too many things about it because of over familiarity. It's not a reflection on the game, just human nature to eventually want to do something else.
Warhammer Online
Almost completely PvP centred game. The leveling isn't bad, quite a lot of good ideas, and a very good conversion of Games Workshop's (modern) vision of the Warhammer world. Anything you do gains you xp apart from crafting so do whatever you like in the game and you will be leveling. Crafting is rubbish in this game though. The main trouble with the game is the lack of variety, it feels like you are doing the same things every time you play, PvP always feels the same no matter what Scenario you do and Public quests are almost always just kill x number of this etc.
Age of Conan
Probably one of the best if you want to role play an authentic fantasy world, the graphics flashy and realistic compared to other MMOs. The main disappointment is the combat system. It doesn't lend itself to PvP and it's too involved for PvE. By that I mean in any MMO you are playing you will be playing lots of hours. You don't really want a combat system that requires as much button presses as a Street Fighter game every fight, it's too demanding.
Don't even think about rolling on a PvP server though, ever since adding rewards for PvP you cannot do anything in a group without getting nailed. Even going to do a dungeon you have to travel to the dungeon as a group as there will be a team of gankers waiting at the dungeon entrance for any poor souls wanting to do some PvE.
Aion
Warcraft 2.0 (almost). Lovely graphics and theme, looks fantastic and some great imagination has gone in to create a fantasy world unlike most other generic fantasy settings. Much of the game feels like Warcraft, in terms of quests and combat. Except the higher level you get and the more experienced you get with the game you will begin to see the cracks in the illusion. Slowly leveling becomes more and more a grind fest like any other Korean MMO. Also combat is nowhere near as cleverly worked out as something like Warcraft. Combat is almost always the same attack cycles with very few spell cool downs to effect what you will do. I am only up to level 30 though so draw from that what you want.
The flying is a nice addition but is a mixed blessing in both PvP and PvE, I wont go in to why, too long to explain, it's just not all good.
